Biological Theories Of Crime Flashcards
What are Biological theories of crime?
The idea that someone is a criminal due to their genetic material; they are ‘born a criminal’
What are the three genetic theories of crime?
Jacobs XYY study, Twin studies, Adoption studies
What are the two physiological theories of crime?
Lombroso and Sheldon
What are the names of the two pairs of twins in the twin studies
Monozygotic (MZ) - identical, from the same egg with the same genetic material
Dizygotic (DZ)
How many twins were found to both be criminal?
MZ = 10/13 DZ = 2/17
What were the chances of both twins being criminal?
50% Mz
20% Dz
What are some criticisms of the Twins study?
Sample size too small - lacks validity
The study was based on the appearance of the twins rather than their actual genetic material
It is difficult to separate the influence of genetics from the influence of social factors
What was Jacobs XYY study?
Looked at chromosome abnormality
The additional Y chromosome can ‘hyper masculinise’ men making them more aggressive, which results in them committing violent crime.
How many more times are XYY males more likely to be criminal than XY males?
10x more likely
What are the criticisms of Jacobs XYY study?
XYY males guilty of crime were found to have committed non violent crimes, such as theft rather than violent crime
What was Lombroso’s idea?
Criminality is linked to a persons physical features
What is the name used to describe the physical features in Lombroso’s study?
‘Atavistic’ features
What are some of the features needed to be considered a criminal by Lombroso?
Large jaw
Large ears
Long arms
Big hands
How many characteristics did men and women need to be born a criminal?
Men = 5 or more Women = 3
What did Lombroso say about tattoos?
Seen as markings of a born criminal
show immortality and insensitivity to physical pain
What are the criticisms of Lombroso’s theory?
Far too simplistic
Ignores other factors such as wealth, diet, health and other social factors
Can be seen as racist
What does William Sheldon link to criminal behaviour?
Person’s physical form
What are were the three body types in Sheldon’s study?
Endomorphic- fat and soft frame (sociable/fun)
Ectomorphic- thin and fragile frame (socially anxious/withdrawn)
Mesomorphic- muscular and hard frame (aggressive/dominant)
What body type was most and least likely to commit crime and why?
Mesomorphic is most likely as their build reflects high testosterone levels that can result in more aggressive behaviour
Ectomorphic least likely
What are the criticisms of Sheldon’s theory?
We cannot assume all mesomorphs are criminal in nature
Doesn’t explain why other body types commit crime in society
What are the two physiological theories of crime?
Sheldon and Lombroso
How does serotonin link to behaviour?
Violent criminal behaviour can be linked to changes in serotonin levels
Lower serotonin levels can cause negative changes in behaviour
